title: Neuroprotective efficacy of prophylactic enteral and parenteral nimodipine treatment in vestibular schwannoma surgery: a comparative study.
abstract: BACKGROUND AND STUDY AIMS/OBJECT: Oral nimodipine improves neurologic outcome after aneurysmal subarachnoid hemorrhage. In addition, the neuroprotective efficacy of nimodipine has been revealed following skull base, laryngeal, and maxillofacial surgery. Pharmacokinetic investigations showed nimodipine to reach higher serum levels following parenteral versus enteral administration. Furthermore, a correlation between nimodipine levels in serum, cerebrospinal fluid, and nerve tissue could be quantified. These observations raise the question whether the proven neuroprotective effect of nimodipine is related to its serum level.
  
  
  METHODS
  A consecutive series of 37 patients with vestibular schwannoma treated with nimodipine from the day before surgery until the seventh postoperative day was analyzed retrospectively. Both groups received standard dosages for enteral (n = 17) and parenteral (n = 20) nimodipine medication. Nimodipine levels were measured in pre- and postoperative serum and cerebrospinal fluid samples. Cochlear and facial nerve functions were documented before surgery, in the early postoperative course, and 1 year after surgery.
  
  
  RESULTS
  Facial nerve outcome was significantly better in the group with parenteral nimodipine medication (p = 0.038). Logistical regression analysis revealed a seven times smaller risk for a deterioration of facial nerve function in the group with parenteral treatment. There was no difference in hearing preservation between both groups despite tumor size tending to be larger in the parenteral group. Intraoperative (p = 0.004), postoperative (p = 0.001), and serum and cerebrospinal fluid (p = 0.024) nimodipine levels were significantly higher following parenteral administration as compared with enteral administration. Both groups were comparable regarding tumor size and extent of resection.
  
  
  CONCLUSIONS
  These results support a dependency of nimodipine's neuroprotective efficacy on its serum levels. Parenteral nimodipine treatment produces higher serum levels and has a higher neuroprotective potency in vestibular schwannoma surgery compared with enteral treatment.
authors.affiliation: Department of Neurosurgery, University of Halle-Wittenberg, Sachsen-Anhalt, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Scheller
authors.affiliation: Institute of Medical Epidemiology, Biostatistics, and Informatics, University of Halle-Wittenberg, Sachsen-Anhalt, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Wienke
authors.affiliation: Department of Neurosurgery, University of Halle-Wittenberg, Sachsen-Anhalt, Germany.
authors.forename: Franziska
authors.initials: F
authors.lastname: Wurm
authors.affiliation: Department of Neurosurgery, University of Halle-Wittenberg, Sachsen-Anhalt, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Simmermacher
authors.affiliation: Department of Neurosurgery, University of Halle-Wittenberg, Sachsen-Anhalt, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Rampp
authors.affiliation: Department of Neurosurgery, University of Halle-Wittenberg, Sachsen-Anhalt, Germany.
authors.forename: Julian
authors.initials: J
authors.lastname: Prell
authors.affiliation: Department of Neurosurgery, University of Halle-Wittenberg, Sachsen-Anhalt, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Rachinger
authors.affiliation: Department of Oral and Maxillofacial Plastic Surgery, University of Halle-Wittenberg, Sachsen-Anhalt, Germany.
authors.forename: Konstanze
authors.initials: K
authors.lastname: Scheller
authors.affiliation: Department of Neurosurgery, University of Halle-Wittenberg, Sachsen-Anhalt, Germany.
authors.forename: Gershom
authors.initials: G
authors.lastname: Koman
authors.affiliation: Department of Neurosurgery, University of Halle-Wittenberg, Sachsen-Anhalt, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Strauss
authors.affiliation: Department of Neurosurgery, University of Halle-Wittenberg, Sachsen-Anhalt, Germany.
authors.forename: Eva
authors.initials: E
authors.lastname: Herzfeld
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003056:Cochlear Nerve / Q000187:drug effects* / Q000502:physiology; D005154:Facial Nerve / Q000187:drug effects* / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009464:Neuroma, Acoustic / Q000601:surgery*; D018696:Neuroprotective Agents / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000627:therapeutic use*; D009553:Nimodipine / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000627:therapeutic use*; D011183:Postoperative Complications / Q000188:drug therapy / Q000517:prevention & control*; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D018696:Neuroprotective Agents; D009553:Nimodipine